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61.
The Dental Subscale of the Children's Fear Survey Schedule (CFSS-DS) is a well-known instrument for assessing dental fear in children. Previous studies have shown that the scale has acceptable reliability and validity. Factor analysis using scores of a group of Finnish schoolchildren resulted in three factors. No other data on the factor structure have been published. In order to report on the factor structure of the Dutch parental version of the CFSS-DS, the present study was undertaken. Factor analysis using scores from a group of Dutch children (n= 150) demonstrated a factor pattern fairly similar to the results found in the Finnish study. Three factors were found: 1) fear of highly invasive dental procedures, 2) fear of less invasive aspects of treatment and 3) fear of medical aspects. Considering that almost all items load substantially (> or =0.20) on more than one factor, it seems that one primary underlying dimension exists: fear of invasive treatment aspects. The CFSS-DS is proposed as a reliable, one-dimensional measure of dental fear. 相似文献
62.
LA Pérula de Torres J Martínez de la Iglesia J Espejo Espejo MV Rubio Cuadrado I Enciso Berge FJ Fonseca del Pozo JM Aranda Lara 《Canadian Metallurgical Quarterly》1997,20(8):425-434
OBJECTIVE: To describe the health status of a population over 60 years and to study their relationship with several socio-demographic variables. DESIGN: A cross-sectional study, population based. SETTINGS: A community. PARTICIPANTS: A randomized sample of 1,103 non institutionalized people over 60 years living in the city of Cordoba (Spain). MEASUREMENTS AND MAIN RESULTS: By mean of a personal interview at home we used the OARS-MFAQ-VE questionnaire. Low self-rated health was associated with the age, to be female sex, a low cultural background, and a low income. Only 5.2% of the study people do not suffered any illness and 56% state that their health problems are major problems for doing their current activities. 4.9% declared to have some degree of physical incapacity. 3.7% of elderly population has an important cognitive deficit. CONCLUSIONS: The majority of elderly people has good health. Age is related with a poor health. Women have more health problems than men. 相似文献
63.
DN Enomoto PT Schellekens SL Yong IJ ten Berge JR Mekkes JD Bos 《Canadian Metallurgical Quarterly》1997,65(1):177-180
The mechanism of action of psoralen plus UVA (PUVA) and photopheresis is not entirely understood. These therapies are assumed to be immunomodulating partly by gradually decreasing leukocyte viability. We investigated whether this delayed form of cell death was due to apoptosis. Untreated and treated (PUVA exposed) leukocytes obtained from six patients with systemic sclerosis and (untreated) leukocytes from healthy control individuals were studied. Qualitative gel electrophoresis and quantitative in situ nick translation analysis of DNA fragmentation was performed. Apoptosis of the treated cells did occur (gel electrophoresis) after 24 h. At t = 0 h, immediately after exposure to PUVA, there was no evidence of DNA fragmentation in the treated cells. The percentage of treated cells undergoing apoptosis was 20-55% at t = 24 h (in situ nick translation). The untreated leukocytes of the patients and the healthy individuals showed no distinctive rise in apoptotic cells. Apoptosis of the leukocytes after PUVA or photopheresis treatment might be a mechanism of action and might explain the therapeutic response. 相似文献
64.
Thomas Kubin Praveen Gajawada Peter Bramlage Stefan Hein Benedikt Berge Ayse Cetinkaya Heiko Burger Markus Schnburg Wolfgang Schaper Yeong-Hoon Choi Manfred Richter 《International journal of molecular sciences》2022,23(3)
Oncostatin M (OSM), a member of the interleukin-6 family, functions as a major mediator of cardiomyocyte remodeling under pathological conditions. Its involvement in a variety of human cardiac diseases such as aortic stenosis, myocardial infarction, myocarditis, cardiac sarcoidosis, and various cardiomyopathies make the OSM receptor (OSMR) signaling cascades a promising therapeutic target. However, the development of pharmacological treatment strategies is highly challenging for many reasons. In mouse models of heart disease, OSM elicits opposing effects via activation of the type II receptor complex (OSMR/gp130). Short-term activation of OSMR/gp130 protects the heart after acute injury, whereas chronic activation promotes the development of heart failure. Furthermore, OSM has the ability to integrate signals from unrelated receptors that enhance fetal remodeling (dedifferentiation) of adult cardiomyocytes. Because OSM strongly stimulates the production and secretion of extracellular proteins, it is likely to exert systemic effects, which in turn, could influence cardiac remodeling. Compared with the mouse, the complexity of OSM signaling is even greater in humans because this cytokine also activates the type I leukemia inhibitory factor receptor complex (LIFR/gp130). In this article, we provide an overview of OSM-induced cardiomyocyte remodeling and discuss the consequences of OSMR/gp130 and LIFR/gp130 activation under acute and chronic conditions. 相似文献
65.
Citric acid is one of the most widely used acids in industry, and its recovery from waste streams is critical. Emulsion liquid membrane (ELM) is one of the most effective recovery methods that has been investigated in recent years. Numerous transport phenomena parameters affect the efficiency of this process. From the process equipment design point of view, optimization based on overall cost is of great importance, and important equipment sizing decisions/constraints must be considered. A physics-based model for a full-scale simulation of ELM systems is very useful. This work is focused on developing and verifying such a model. A coupled particle/mixture simulation was carried out in this work, and the modelling results were fitted on the experimental data. The novelty of this modelling work is physics-based results based on the system's geometry and its effects on the mass transfer resistances. Since the model is physics-based, the model is capable of simulating similar systems with any geometry or experimental conditions. 相似文献
66.
Rapid detection of airborne fungal and bacterial spores would enable public agencies to respond quickly and appropriately to intentional releases of hazardous aerosols. Automated analysis of microscope images and automated detection of near-monodisperse peaks in aerosol size distribution data offer complementary approaches to traditional methods for the identification and counting of fungal and bacterial spores. First, spores of the fungus Scopulariopsis brevicaulis were aerosolized in a chamber and then collected with a slit impactor; later, digital microscope images were analyzed manually to determine spore cluster distributions. The images also were analyzed with ImageJ, a program that automatically outlined objects and measured Feret's diameter, area, perimeter, and circularity. These characteristics were used to identify spore clusters automatically using two data analysis methods. Second, a computer program was developed to discriminate near-monodisperse bioaerosol peaks from those for polydisperse ambient particulate matter (PM) and was successfully tested using simulated and real aerosol mixtures. The observed agreement between manual and automated spore counts and the ability to detect spore peaks suggest that it may be possible to develop a system to recognize intentional releases rapidly through examination of particle morphology and size distributions. The peak detection procedure is potentially the fastest technique when used with real-time instrument data, but assumes that intentional releases would consist of large numbers of uniformly sized particles in the respirable size range. Copyright 2012 American Association for Aerosol Research 相似文献
67.
A method has been developed to estimate average concentrations and size distributions with a miniature passive aerosol sampler. To use the passive sampler, one exposes it to an environment for a period of hours to weeks. The passive sampler is intended to monitor ambient, indoor, or occupational aerosols and has potential utility as a personal sampler. The sampler is inexpensive and easy to operate and is capable of taking long-term samples to investigate chronic exposures. After sampling, the passive sampler is covered and brought to the lab. Scanning electron microscopy (SEM) and automated image analysis are used to count and size collected particles with dp 相似文献
68.
Zdenek Nejedlý John L. Campbell Jeff Brook Robert Vet Robert Eldred 《Aerosol science and technology》2013,47(1):96-108
The GAViM program provides fine particulate and visibility data for several remote locations in Canada. Two long-term intercomparison studies between the GAViM and a major U.S. aerosol monitoring network, IMPROVE, were used to evaluate the uncertainty in the analytical data produced by proton induced x-ray emission (PIXE), proton elastic scattering analysis (PESA), and gravimetric analysis. GAViM and IMPROVE agreed well for elements from Fe to Zn where PIXE is the most sensitive; the relative difference between the 2 networks for Fe and Zn was <2%. Some lighter elements, e.g., sodium or sulphur, revealed a difference of 10-20%. Furthermore, an empiric conversion scheme for the GAViM absorption data produced by the laser integrated plate method (LIPM) was derived from the comparison to the IMPROVE thermal/optical reflectance (TOR) data. This conversion depends on the aerosol composition and is therefore site specific. It allows estimation of the elemental carbon concentrations from the historic raw light absorption values obtained by LIPM. If the mass attenuation coefficient of the fine aerosol collected at the 2 remote GAViM sites is assumed to be equal to 10 m 2 /g, then the results imply that the light absorption coefficient measured by LIPM is generally higher than the true value by up to a factor of 1.3 or 1.8, respectively. In both cases, LIPM overestimated the black carbon content, mostly for the lightly loaded samples. 相似文献
69.
Effect of 18∶1n−9, 20∶5n−3, and 22∶6n−3 on lipid accumulation and secretion by atlantic salmon hepatocytes 总被引:1,自引:0,他引:1
We have studied the effects of dietary FA on the accumulation and secretion of [3H]glycerolipids by salmon hepatocytes in culture. Atlantic salmon were fed diets supplemented with either 100% soybean oil
(SO) or 100% fish oil (FO), and grew from an initial weight of 113±5 g to a final weight of 338 ±19 g. Hepatocytes were isolated
from both dietary groups and incubated with [3H]glycerol in an FA-free medium; a medium supplemented with 0.75 mM of one of three FA—18∶1n−9, 20∶5n−3, or 22∶6n−3—or a medium
supplemented with 0.75 mM of the sulfur-substituted FA analog tetradecylthioacetic acid (TTA), which cannot undergo β-oxidation.
Incubations were allowed to proceed for 1,2,6, or 24 h. The rate of the secretion of radioactive glycerolipids with no FA
added was 36% lower from hepatocytes isolated from fish fed the FO diet than it was from hepatocytes isolated from fish fed
the SO diet. Hepatocytes incubated with 18∶1n−9 secreted more [3H]TAG than when incubated with no FA, whereas hepatocytes incubated with 20∶5n−3 or TTA secreted less labeled TAG than when
incubated with no FA. This observation was independent of the feeding group. Hepatocytes incubated with 22∶6n−3 secreted the
highest amounts of total [3H]glycerolipids compared with the other treatments, owing to increased secretion of phospholipids and mono- and diacylglycerols
(MDG). In contrast, the same amounts of [3H]TAG were secreted from these cells as from cells incubated in an FA-free medium. The lipid-lowering effect of FO is thus
independent of 22∶6n−3, showing that 20∶5n−3 is the FA that is responsible for the lipid-lowering effect. The ratio of TAG
to MDG in lipids secreted from hepatocytes to which 20∶5n−3 or TTA had been added was lower than that in lipids secreted from
hepatocytes incubated with 18∶1n−9 or 22∶6n−3, suggesting that the last step in TAG synthesis was inhibited. Morphometric
measurements revealed that hepatocytes incubated with 20∶5n−3 accumulated significantly more cellular lipid than cells treated
with 18∶1n−9, 22∶6n−3, TTA, or no treatment. The area occupied by mitochondria was also greater in these cells. The present
study shows that dietary FO reduces TAG secretion from salmon hepatocytes and that 20∶5n−3 mediates this effect. 相似文献
70.
Mark A. Andrews Garret D. Figuly John S. Chapman Todd W. Hunt C. Darrel Glunt Jeff A. Rivenbark H. Keith Chenault 《应用聚合物科学杂志》2011,119(6):3244-3252
Aqueous dispersions (0.1 wt %) of hydrogels 1 and 5 —formed by crosslinking polyallylamine hydrochloride (MW 60,000) with aldaric acid derivatives, diethyl L ‐tartrate and N,N′‐bis(methoxycarbonylmethyl)‐D ‐glucaramide, respectively—exhibited complete (log 5) kill within 4 h of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans suspended in culture medium. This antimicrobial activity was much higher than that of uncrosslinked polyallylamine (1 wt % killed only 75% of E. coli in 24 h). When dispersed at 10 and 100 ppm, hydrogel 5 displayed complete (log 5) kill of E. coli within 30–60 and 15 min, respectively. Hydrogels 1 and 5 were active against S. aureus and Salmonella choleraesuis dried on hard stainless steel surfaces and accelerated the deaths of E. coli, P. aeruginosa, S. aureus, and C. albicans in a model skin cream formulation. A 0.8% aqueous dispersion of hydrogel 5 was also effective as a hand sanitizer, killing 99.7% of Serratia marcescens on human hands within 5 min. Hydrogels 1 and 5 caused no dermal irritation or allergic contact sensitization under the conditions of a human repeat insult patch test. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献